I used to say to my boss: ... it's not a bug it's a feature! I'm kidding :) By the way, even in this "design choice", al least the first test scenario is a bug (described in the first half on the Jira BUG): http://pastebin.freeswitch.org/17906 Moreover this "by design" behavior create some problem not only for transcoding issue but also for fax upspeed codec modification (no T38). Years ago, when hardware resources where poor, I had a lot of discussions with my colleagues to avoid the allocation of transcoding resources on our softswitch and we always ended up to use a transcoding resource if and only if it's really needed, if the endpoints can speak the same language let them do all the stuff. I know easy to say but ... Back to FS, what I think is we miss an endpoint independent codec negotiation signaling. I mean something like we have in the call setup phase via "absolute_codec_string" / "ep_codec_string" / SWITCH_ORIGINATOR_CODEC_VARIABLE. As I'm playing/prototyping a new endpoint module I used these channel variable to successfully interworking with SIP endpoint gateway in codec passthrough... but now that the test-suite is going over the SIP basic call codec modification I found that "by design problem". In the (working) spare time I'm trying to write a patch to extend the core interworking opening the way I suggested few lines over. As I'm very new to FS, for now it's a very embryonal and poor implementation in my opinion, but enough for the endpoint module prototype evaluation. I hope to give that back to you if I can find more time to move the patch to a presentable level. Giovanni -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org on behalf of Brian West Sent: Wed 12/21/2011 6:30 PM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Sofia late-negotiation onre-INVITE(codec-modification) I don't think this is a bug... I think its by design. /b On Dec 21, 2011, at 11:26 AM, Visciano Giovanni wrote:
I've opened a BUG. http://jira.freeswitch.org/browse/FS-3739
I don't know what's you FS configuration. What I know is: - SIP "media proxy mode" is OK. - re-INVITE for codec modification to image T.38 (t38-passthrough) is OK in all SIP "media mode".
The "late_negotiation" + "inherit_codec" trick to avoid transcoding in a Back2Back (that is no media proxy) configuration works only for the very first call setup SDP offer/answer. http://wiki.freeswitch.org/wiki/Codec_negotiation
Once the call is established, further codec modification via re-INVITE are usually closed on each leg (except for t38) and this can led to transcoding (and obvious errors if you can't or don't want to transcode).
Hope this helps you find out your problem.
Giovanni
-- Brian West FreeSWITCH Solutions, LLC Phone: +1 (918) 420-9266 Fax: +1 (918) 420-9267 brian@freeswitch.org http://www.freeswitch.org Internet Email Confidentiality Footer ----------------------------------------------------------------------------------------------------- La presente comunicazione, con le informazioni in essa contenute e ogni documento o file allegato, e' rivolta unicamente alla/e persona/e cui e' indirizzata ed alle altre da questa autorizzata/e a riceverla. Se non siete i destinatari/autorizzati siete avvisati che qualsiasi azione, copia, comunicazione, divulgazione o simili basate sul contenuto di tali informazioni e' vietata e potrebbe essere contro la legge (art. 616 C.P., D.Lgs n. 196/2003 Codice in materia di protezione dei dati personali). Se avete ricevuto questa comunicazione per errore, vi preghiamo di darne immediata notizia al mittente e di distruggere il messaggio originale e ogni file allegato senza farne copia alcuna o riprodurne in alcun modo il contenuto. This e-mail and its attachments are intended for the addressee(s) only and are confidential and/or may contain legally privileged information. If you have received this message by mistake or are not one of the addressees above, you may take no action based on it, and you may not copy or show it to anyone; please reply to this e-mail and point out the error which has occurred. -----------------------------------------------------------------------------------------------------